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<h1>Source code for searx.plugins.unit_converter</h1><div class="highlight"><pre>
<span></span><span class="c1"># SPDX-License-Identifier: AGPL-3.0-or-later</span>
<span class="sd">"""A plugin for converting measured values from one unit to another unit (a</span>
<span class="sd">unit converter).</span>
<span class="sd">The plugin looks up the symbols (given in the query term) in a list of</span>
<span class="sd">converters, each converter is one item in the list (compare</span>
<span class="sd">:py:obj:`ADDITIONAL_UNITS`). If the symbols are ambiguous, the matching units</span>
<span class="sd">of measurement are evaluated. The weighting in the evaluation results from the</span>
<span class="sd">sorting of the :py:obj:`list of unit converters<symbol_to_si>`.</span>
<span class="sd">"""</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">__future__</span><span class="w"> </span><span class="kn">import</span> <span class="n">annotations</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">typing</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">re</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">babel.numbers</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">flask_babel</span><span class="w"> </span><span class="kn">import</span> <span class="n">gettext</span><span class="p">,</span> <span class="n">get_locale</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.wikidata_units</span><span class="w"> </span><span class="kn">import</span> <span class="n">symbol_to_si</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.plugins</span><span class="w"> </span><span class="kn">import</span> <span class="n">Plugin</span><span class="p">,</span> <span class="n">PluginInfo</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.result_types</span><span class="w"> </span><span class="kn">import</span> <span class="n">EngineResults</span>
<span class="k">if</span> <span class="n">typing</span><span class="o">.</span><span class="n">TYPE_CHECKING</span><span class="p">:</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.search</span><span class="w"> </span><span class="kn">import</span> <span class="n">SearchWithPlugins</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.extended_types</span><span class="w"> </span><span class="kn">import</span> <span class="n">SXNG_Request</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">searx.plugins</span><span class="w"> </span><span class="kn">import</span> <span class="n">PluginCfg</span>
<span class="n">name</span> <span class="o">=</span> <span class="s2">""</span>
<span class="n">description</span> <span class="o">=</span> <span class="n">gettext</span><span class="p">(</span><span class="s2">""</span><span class="p">)</span>
<span class="n">plugin_id</span> <span class="o">=</span> <span class="s2">""</span>
<span class="n">preference_section</span> <span class="o">=</span> <span class="s2">""</span>
<span class="n">CONVERT_KEYWORDS</span> <span class="o">=</span> <span class="p">[</span><span class="s2">"in"</span><span class="p">,</span> <span class="s2">"to"</span><span class="p">,</span> <span class="s2">"as"</span><span class="p">]</span>
<div class="viewcode-block" id="SXNGPlugin">
<a class="viewcode-back" href="../../../dev/plugins/unit_converter.html#searx.plugins.unit_converter.SXNGPlugin">[docs]</a>
<span class="k">class</span><span class="w"> </span><span class="nc">SXNGPlugin</span><span class="p">(</span><span class="n">Plugin</span><span class="p">):</span>
<span class="w"> </span><span class="sd">"""Convert between units. The result is displayed in area for the</span>
<span class="sd"> "answers".</span>
<span class="sd"> """</span>
<span class="nb">id</span> <span class="o">=</span> <span class="s2">"unit_converter"</span>
<span class="k">def</span><span class="w"> </span><span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">plg_cfg</span><span class="p">:</span> <span class="s2">"PluginCfg"</span><span class="p">)</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span>
<span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">(</span><span class="n">plg_cfg</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">info</span> <span class="o">=</span> <span class="n">PluginInfo</span><span class="p">(</span>
<span class="nb">id</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">id</span><span class="p">,</span>
<span class="n">name</span><span class="o">=</span><span class="n">gettext</span><span class="p">(</span><span class="s2">"Unit converter plugin"</span><span class="p">),</span>
<span class="n">description</span><span class="o">=</span><span class="n">gettext</span><span class="p">(</span><span class="s2">"Convert between units"</span><span class="p">),</span>
<span class="n">preference_section</span><span class="o">=</span><span class="s2">"general"</span><span class="p">,</span>
<span class="p">)</span>
<div class="viewcode-block" id="SXNGPlugin.post_search">
<a class="viewcode-back" href="../../../dev/plugins/unit_converter.html#searx.plugins.unit_converter.SXNGPlugin.post_search">[docs]</a>
<span class="k">def</span><span class="w"> </span><span class="nf">post_search</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">request</span><span class="p">:</span> <span class="s2">"SXNG_Request"</span><span class="p">,</span> <span class="n">search</span><span class="p">:</span> <span class="s2">"SearchWithPlugins"</span><span class="p">)</span> <span class="o">-></span> <span class="n">EngineResults</span><span class="p">:</span>
<span class="n">results</span> <span class="o">=</span> <span class="n">EngineResults</span><span class="p">()</span>
<span class="c1"># only convert between units on the first page</span>
<span class="k">if</span> <span class="n">search</span><span class="o">.</span><span class="n">search_query</span><span class="o">.</span><span class="n">pageno</span> <span class="o">></span> <span class="mi">1</span><span class="p">:</span>
<span class="k">return</span> <span class="n">results</span>
<span class="n">query</span> <span class="o">=</span> <span class="n">search</span><span class="o">.</span><span class="n">search_query</span><span class="o">.</span><span class="n">query</span>
<span class="n">query_parts</span> <span class="o">=</span> <span class="n">query</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s2">" "</span><span class="p">)</span>
<span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">query_parts</span><span class="p">)</span> <span class="o"><</span> <span class="mi">3</span><span class="p">:</span>
<span class="k">return</span> <span class="n">results</span>
<span class="k">for</span> <span class="n">query_part</span> <span class="ow">in</span> <span class="n">query_parts</span><span class="p">:</span>
<span class="k">for</span> <span class="n">keyword</span> <span class="ow">in</span> <span class="n">CONVERT_KEYWORDS</span><span class="p">:</span>
<span class="k">if</span> <span class="n">query_part</span> <span class="o">==</span> <span class="n">keyword</span><span class="p">:</span>
<span class="n">from_query</span><span class="p">,</span> <span class="n">to_query</span> <span class="o">=</span> <span class="n">query</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">keyword</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span>
<span class="n">target_val</span> <span class="o">=</span> <span class="n">_parse_text_and_convert</span><span class="p">(</span><span class="n">from_query</span><span class="o">.</span><span class="n">strip</span><span class="p">(),</span> <span class="n">to_query</span><span class="o">.</span><span class="n">strip</span><span class="p">())</span>
<span class="k">if</span> <span class="n">target_val</span><span class="p">:</span>
<span class="n">results</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">results</span><span class="o">.</span><span class="n">types</span><span class="o">.</span><span class="n">Answer</span><span class="p">(</span><span class="n">answer</span><span class="o">=</span><span class="n">target_val</span><span class="p">))</span>
<span class="k">return</span> <span class="n">results</span></div>
</div>
<span class="c1"># inspired from https://stackoverflow.com/a/42475086</span>
<span class="n">RE_MEASURE</span> <span class="o">=</span> <span class="sa">r</span><span class="s1">'''</span>
<span class="s1">(?P<sign>[-+]?) # +/- or nothing for positive</span>
<span class="s1">(\s*) # separator: white space or nothing</span>
<span class="s1">(?P<number>[\d\.,]*) # number: 1,000.00 (en) or 1.000,00 (de)</span>
<span class="s1">(?P<E>[eE][-+]?\d+)? # scientific notation: e(+/-)2 (*10^2)</span>
<span class="s1">(\s*) # separator: white space or nothing</span>
<span class="s1">(?P<unit>\S+) # unit of measure</span>
<span class="s1">'''</span>
<span class="k">def</span><span class="w"> </span><span class="nf">_parse_text_and_convert</span><span class="p">(</span><span class="n">from_query</span><span class="p">,</span> <span class="n">to_query</span><span class="p">)</span> <span class="o">-></span> <span class="nb">str</span> <span class="o">|</span> <span class="kc">None</span><span class="p">:</span>
<span class="c1"># pylint: disable=too-many-branches, too-many-locals</span>
<span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">from_query</span> <span class="ow">and</span> <span class="n">to_query</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">None</span>
<span class="n">measured</span> <span class="o">=</span> <span class="n">re</span><span class="o">.</span><span class="n">match</span><span class="p">(</span><span class="n">RE_MEASURE</span><span class="p">,</span> <span class="n">from_query</span><span class="p">,</span> <span class="n">re</span><span class="o">.</span><span class="n">VERBOSE</span><span class="p">)</span>
<span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">measured</span> <span class="ow">and</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'number'</span><span class="p">),</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'unit'</span><span class="p">)):</span>
<span class="k">return</span> <span class="kc">None</span>
<span class="c1"># Symbols are not unique, if there are several hits for the from-unit, then</span>
<span class="c1"># the correct one must be determined by comparing it with the to-unit</span>
<span class="c1"># https://github.com/searxng/searxng/pull/3378#issuecomment-2080974863</span>
<span class="c1"># first: collecting possible units</span>
<span class="n">source_list</span><span class="p">,</span> <span class="n">target_list</span> <span class="o">=</span> <span class="p">[],</span> <span class="p">[]</span>
<span class="k">for</span> <span class="n">symbol</span><span class="p">,</span> <span class="n">si_name</span><span class="p">,</span> <span class="n">from_si</span><span class="p">,</span> <span class="n">to_si</span><span class="p">,</span> <span class="n">orig_symbol</span> <span class="ow">in</span> <span class="n">symbol_to_si</span><span class="p">():</span>
<span class="k">if</span> <span class="n">symbol</span> <span class="o">==</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'unit'</span><span class="p">):</span>
<span class="n">source_list</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">si_name</span><span class="p">,</span> <span class="n">to_si</span><span class="p">))</span>
<span class="k">if</span> <span class="n">symbol</span> <span class="o">==</span> <span class="n">to_query</span><span class="p">:</span>
<span class="n">target_list</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">si_name</span><span class="p">,</span> <span class="n">from_si</span><span class="p">,</span> <span class="n">orig_symbol</span><span class="p">))</span>
<span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">source_list</span> <span class="ow">and</span> <span class="n">target_list</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">None</span>
<span class="n">source_to_si</span> <span class="o">=</span> <span class="n">target_from_si</span> <span class="o">=</span> <span class="n">target_symbol</span> <span class="o">=</span> <span class="kc">None</span>
<span class="c1"># second: find the right unit by comparing list of from-units with list of to-units</span>
<span class="k">for</span> <span class="n">source</span> <span class="ow">in</span> <span class="n">source_list</span><span class="p">:</span>
<span class="k">for</span> <span class="n">target</span> <span class="ow">in</span> <span class="n">target_list</span><span class="p">:</span>
<span class="k">if</span> <span class="n">source</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">==</span> <span class="n">target</span><span class="p">[</span><span class="mi">0</span><span class="p">]:</span> <span class="c1"># compare si_name</span>
<span class="n">source_to_si</span> <span class="o">=</span> <span class="n">source</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span>
<span class="n">target_from_si</span> <span class="o">=</span> <span class="n">target</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span>
<span class="n">target_symbol</span> <span class="o">=</span> <span class="n">target</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span>
<span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">source_to_si</span> <span class="ow">and</span> <span class="n">target_from_si</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">None</span>
<span class="n">_locale</span> <span class="o">=</span> <span class="n">get_locale</span><span class="p">()</span> <span class="ow">or</span> <span class="s1">'en_US'</span>
<span class="n">value</span> <span class="o">=</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'sign'</span><span class="p">)</span> <span class="o">+</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'number'</span><span class="p">)</span> <span class="o">+</span> <span class="p">(</span><span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'E'</span><span class="p">)</span> <span class="ow">or</span> <span class="s1">''</span><span class="p">)</span>
<span class="n">value</span> <span class="o">=</span> <span class="n">babel</span><span class="o">.</span><span class="n">numbers</span><span class="o">.</span><span class="n">parse_decimal</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">locale</span><span class="o">=</span><span class="n">_locale</span><span class="p">)</span>
<span class="c1"># convert value to SI unit</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">source_to_si</span><span class="p">,</span> <span class="p">(</span><span class="nb">float</span><span class="p">,</span> <span class="nb">int</span><span class="p">)):</span>
<span class="n">value</span> <span class="o">=</span> <span class="nb">float</span><span class="p">(</span><span class="n">value</span><span class="p">)</span> <span class="o">*</span> <span class="n">source_to_si</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">value</span> <span class="o">=</span> <span class="n">source_to_si</span><span class="p">(</span><span class="nb">float</span><span class="p">(</span><span class="n">value</span><span class="p">))</span>
<span class="c1"># convert value from SI unit to target unit</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">target_from_si</span><span class="p">,</span> <span class="p">(</span><span class="nb">float</span><span class="p">,</span> <span class="nb">int</span><span class="p">)):</span>
<span class="n">value</span> <span class="o">=</span> <span class="nb">float</span><span class="p">(</span><span class="n">value</span><span class="p">)</span> <span class="o">*</span> <span class="n">target_from_si</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">value</span> <span class="o">=</span> <span class="n">target_from_si</span><span class="p">(</span><span class="nb">float</span><span class="p">(</span><span class="n">value</span><span class="p">))</span>
<span class="k">if</span> <span class="n">measured</span><span class="o">.</span><span class="n">group</span><span class="p">(</span><span class="s1">'E'</span><span class="p">):</span>
<span class="c1"># when incoming notation is scientific, outgoing notation is scientific</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">babel</span><span class="o">.</span><span class="n">numbers</span><span class="o">.</span><span class="n">format_scientific</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">locale</span><span class="o">=</span><span class="n">_locale</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">babel</span><span class="o">.</span><span class="n">numbers</span><span class="o">.</span><span class="n">format_decimal</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">locale</span><span class="o">=</span><span class="n">_locale</span><span class="p">,</span> <span class="nb">format</span><span class="o">=</span><span class="s1">'#,##0.##########;-#'</span><span class="p">)</span>
<span class="k">return</span> <span class="sa">f</span><span class="s1">'</span><span class="si">{</span><span class="n">result</span><span class="si">}</span><span class="s1"> </span><span class="si">{</span><span class="n">target_symbol</span><span class="si">}</span><span class="s1">'</span>
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